I would go with the 18. I think leaving 1 cm is too snug. I prefer at least 1.5 cm, which I have read is a comfortable fit. Cartier always seems to want you to go with that snug fit. I reserve the snug fit for men, not women. I was advised the snug fit over the phone by Cartier as well, but I used the wrist sizer from the Cartier site and went against what I was advised and am very happy.
That's exactly how I was feeling about it too. And despite how it's meant to be worn (tighter fit) I went with my gut feeling and switched to size 18. Zero regrets! In fact, I am now wondering how in the world did I ever think 18 was too big. I wouldn't even mind to have 19, but that might be pushing it. LOL
Thank you for your comment, it helped push me and I am so glad I switched to a larger size. Thanks again!
My wrist is also 6.25 and I wish they had size 17.5 .. for some reason 17 was too tight while 18 too loose. Ugh.
Well, I ended up switching from size 17 to size 18, and I do not regret it at all! I love size 18, and would even be curious how 19 would fit. Anyway, if you're in between sizes (17 too small and 18 feels too big) I would recommend 18. When I tried 18 the first few times, it felt big and 17 felt just right. But after having them on for an hour I realized 18 is perfect and 17 too small. Hope this helps.
Also, for anyone wondering and reading this in the future, if you prefer a cuff look where the love sits just a bit above your wrist bone and not much movement, then size up 1cm for a tighter fit like Cartier recommends. But if you love a bangle look and want a little movement for a more casual, carefree look, size up 2cm (or even 3cm if you really love the bangle to sit in the middle of your arm).
I was confused about the sizing for the longest time, because I was clashing with two different looks, how the love bracelet is meant to be worn (cuff style around the wrist) and what I personally like (bangle style, higher up on my arm). Most of the photos circulating online (when you google it while trying to get an idea how it is supposed to look) people drag the bracelet down to their wrist to photograph it, and big or small fit, it always ends up looking right. But when you start trying it higher up on your arm, that's where personal preferences kick in. Just listen to your inner feeling agains what it's "supposed" to look like.
I'd recommend browsing mod shots photos of any bracelet in general and see where you personally like the location of bracelet on the arm, what appeals to you the most. Then go and pick the size that sits similar to your preferred spot on the arm. Hope this helps someone!
